It is the summer of 1851. An English family is making a romantic journey by paddle-steamer on the Rhine, and Charlotte's imagination is stretched to the limit - one might almost say, to the breaking point.She is the unmarried sister of the Reverend Charles Morrison with whose family she is travelling. As they board the boat, Charlotte suddenly mistakes a passenger for the man she gave up years ago, at her brother's insistence. From that moment, this extraordinarily evocative novel creates an aura of romantic tension that is a compelling as it is mysterious. Charlotte's interior passion is counterpointed with the stifling manners of the time, and inexorably she is drawn closer to confrontation with the passenger, and herself.